Process for producing clear lightcolored, water-soluble sulphonation products of mineral oil



Patented June 2 8 1938 PROCESS FOR PRODUCING CLEAR'LIGHT- COLORED,WATER-SOLUBLE SULPHONA-' TION PRODUCTS OF MINERAL OIL Erich'ArnoldWernicke, Hamburg, Germany No Drawing. Application January 9, 1934, Se-

rial No. 705,918. In .1933

This invention relates to a process for the pr duction of sulphonationproducts from sulphurbearing mineral oils, tar oils, and the like, i. e.

from oils containing about 2 per cent and more 5 of sulphur.

sulphonation products from mineral oils, tar oils, etc. are used formany purposes, as for instance for the preparation of. emulsions, forgeneral technical purposes, or for the manufacture of pharmaceuticalpreparations and the like.

The products of this kind, obtained from sulphurbearing oils, have aspecial importance in this respect.

These products are usuallyof a very dark color and not clear, even inthin layers, because in their production the sulphuric acid exerts alsoa resinifying action due :to oxidation or condensation efiects, apartfrom the sulphonating action itself. The dark color of the sulphonationprod-- uct is disadvantageous for many purposes and the odor generallyis regarded as disagreeable.

Various processes for refinement of oils to remove coloring impuritiesare known per se. In 1 the instant invention, however, the purpose is toremove the coloring ingredients without, at the same time, materiallyreducing the original sulphur content of the oils to be treated, whereasthe prior art was directed also to the most complete removal of thesulphur, and. that was the principal scope or one of the purposes of therefinement. I A noteworthy difference over the refinement processes thusfar known lies in the fact that'the materials in question cannotstrictly be considered as hydrocarbon oils in view of their high sulphurcontent. A sulphur content, for instance, of 10% corresponds toa-content of sulphur compounds of approximately 50-60%, so that theexperiences had with oils having less than 2% of sulphur, which canstill be fairly classified as hydrocarbons, cannot simply be applied tothe sulphur oils involved herein.

It must also be emphasized that usually the original color of the oil isnot controlling. Thus,

' :5 a light-colored oil may, in the subsequentsulphonation, produce adark resinous product. It is, therefore, an object to remove, bypre-refinement, all those oil substances which would cause a darkcoloration of the final sulphonation product, retaining, nevertheless,as much as possible the original sulphur compounds.

The present invention solves this task in such a manner that the oils ortheir distillates, or singular fractions, are liberated, by a chemical65 pre-refinement, from the ingredients that might Germany January 11,

5 Claims. (01. 196-40) cause a dark coloration of the end product in thesulphonation process. The main part of the sulphur compounds remains,however, in the oils,

and the oils are then carefully sulphonated under cooling or with partlyconcentrated sulphuric 5 acid, or with the use of a suitable diluent,whereupon the further process is carried out in-the usual manner. In thesulphonation procedure several of the indicated processes may becombined with each other.

- The ore-refinement can be carriedv out, for instance, with soda lye orwith sulphuric acid,

the concentration of which has to be calculated from the character ofthe oil put into process,

so that on the one hand the resinifying substances will be removed asfar as possible and, on the other hand, that no material degree ofsulphonation or removal of sulphur compounds will take place. Thepre-refinement can also be carried out with other known refining agentswhich may be used either alone or combined, depending on the chemicalcharacter of the oil, thus, for instance, with potash lye, aluminumchloride, phosphoric acid, fullers earth, bleaching clay, and

the like.

In the careful sulphonation process that part of the oil resulting frompreceding sulphonations which cannot further be sulphonated or treatedwith sulphuric acid may serve as suitable diluent.

Depending on the thoroughness of the prerefinement and depending furtheron 'the'degree of care observed in the sulphonation process, afterneutralizing the sulphonation mixture and separating the undissolvedportions of the oil, transparent, clear water-soluble products of 35light-yellow to brown color are obtained which do not generally imparttheir color to other substances when mixed with them, whereas withoutthis treatment much darker, non-transparent," mostly black-brownproducts are obtained.

Under favorable circumstances many of the products of this process maybe obtained more or less completely or practically odorles Following thefirst careful sulphonation this can be repeated several times withsulphuric acid of graduated increase in strength, so that eachsulphonation process can, in a sense, be regarded as pre-refinement forthe sulphonation with the g 4 next-following stronger acid. The acidconcentration to be employed in the successive sulphonation steps isdownwardly limited by the acid concentration used in the preceding step;there'is' no upward limit and, observing the neces-, sary care in otherrespects, the concentrations may be increased up to the stage of fumingsul- 55 desired consistency by adding water orby evaporation. Theremoval of sulphates can be carried out in any well known manner, eitherbefore or after the neutralization, for instance by dialysis or byextraction with solvents.

According to this invention sulphur-bearing petroleum or other oils, forinstance from Italian mineral coal, Middle-German brown coal, South-German bituminous shale, orsimilar combinations or mixtures may be usedwith equal advantage for the manufacture of such sulphonation products.Analogous deposits of coal-like materials which are equally suitable forthe process according to this invention on account of theirsulphurcontent are found in all parts of the world. Practically it is,of course, preferable to.

begin with the distillates because the refinement is thereby simplified.

Example 1 As starting material a distilled Italian mineral coal-tar,having the following characteristics, is used: specific weight at 15 C.about 0.9; sulphur content 8.8%; boiling points about -250. 100 grams ofthis oil are pre-refined with soda lye of 39 B., sulphuric acid of 70%H2804 and fullers earth. The sulphur content after the prerefinement is10.22%.

The refinedoil is now sulphonated with about 60 cc. sulphuric acid of90% H2804 under stirring and cooling at 0 C. The sulphonation mixture isrun into water, and sulpho-acid and oil are then neutralized withammonia. After separating the oil, the product is evaporated to a watercontent of 41.24%. 10 grams are obtained of this product, which, in thiscondition, contains 6.84% of ammonium sulphate and 9.57% of sulphur. Theorganic substance .is 51.92% including 15.24% of sulphur. It has beencalculated that the oil substance which has been sulphonated contains11.01% of organic sulphur. The product is light-brown, transparent andclearly watersoluble. The reaction products of the oil and sulphuricacid obtained in the end product are true sulpho-acids and not estersbecause the latter would be split by the strong heating which takesplace in the dilution of the sulphonation product with water and in theevaporation of the water from the neutralized product.

Example 2 As starting material a distilled Italian mineral coal-tar isused having the following character-,

istics: specific weight at 15 C. 0.890; sulphur content 7.0%; boilinganalysis:

v Percent 101-200 54.3 200-269 531 grams of this oil are pre-refinedwith 35% soda lye, 85% phosphoric acid and fullers earth;

with ammonia. After separating the oil, the product is then evaporatedto a water content of 42%. 69 grams of this product are obtained. Inthis condition it contains 11% of ammonium sill-- phate and 10.62% ofsulphur. The organic substance therein is 47.%, including 16.92% ofsulphur. It has been calculated that the oil' substance which has' beensulphonated contains 10.38% of organic sulphur. The product is light--brown, transparent and clearly water-soluble.

Example 3.

As starting material a distilled Mid-German brown coal-gas-light oil isused having the fol-. lowing characteristics: specific weight at 15 C.0.850; sulphur content 6.0%; boiling analysis:

. Percent 80 to 2.5 100 to 150 r 33 150 to 200 92 I 500 grams of thisoil are-pre-refined with 50% potash lye and 50% sulphuric acid. Thesulphur content of the oil after this pre-refinement still is 5.6%. Therefined oil is now sulphonated with about 500 cc. sulphuric acid (pureconcentrated) under stirring and cooling at about 0 .C. The sulphonationmixture is run into water and neutralized with ammonia. After removal ofthe unaffected part of the oil, having become separated by the dilutionwith water, the product is evap- Example 4 As starting material adistilled Tyrolean shale oil is used having the followingcharacteristics:

specific weight at 15 C. 0.885; sulphur content 11.3% boiling analysis:

Percent 80 to 100 1.8 100 to 200 61.0 200 to 300 1 94.1

524 grams of this oil are pre-refined with waterfree aluminum chloride,35% soda lye and fullers earth. The sulphur content of the oil afterthis pro-refinement is still 11%. The refined oil is now sulphonatedwith about 425 cc. sulphuric acid (pure concentrated) under stirring andcooling at about -'5 C. Thesulphonation mixture is run into water andsulpho-acid and oil are neutralized with ammonia. After removal of theunafiected part of the oil, having become separated by the dilution withwater, the product is evaporated to a water content of 30.5%. i grams ofthis product are obtained. It contains in this condition 4.77% ofammonium sulphate and 14.80% of sulphur. The organic substance thereinis 64.73%, including 21.07% of sulphur. It has been calculated that thesulphonated oil substance contains 17.53%, of organic sulphur. The

product is light-brown, transparent and clearly water-soluble.

' Example 5 As starting material a distilled Tyrolean shale oil is usedrefined with 35% soda'lye, 70% sullowing characteristics: specificweight at 15 C. 0.894; sulphur content 11.45%; boiling analysis:

Percent 130 to 200 '58 200 to 287 96.5

7.15 kg. of this oil are sulphonated with 16 1. sulphuric acid(technical 66 B.) under stirring at a temperature of about -8 C. The$111- phonation mixture is run into water and sulphoacid and oil areneutralized with ammonia. After removal of the unaffected part, havingbe-' come separated by the dilution with water, the product isevaporated to a water content of 24.25%. 1.83 kg. of this product areobtained. It contains in this condition 7.33% of ammonium sulphate and14.87% of sulphur. The organic substance therein is 68.42%, including19.13% of sulphur. The sulphonated oil substance contains 15.04% oforganic sulphur. The product is light-brown, transparent and clearlywatersoiuble.

463 grams of the oil, separated by the dilution of the sulphonationmixture with water, having a specific weight of 0.926 at 15 C., arediluted with an equal volume of petroleum and with 500 cc. of sulphuricacid (16 weight percent of 66 B. technical acid +84 weight percent oftechnical fuming acid with 18% of $03) under stirring at a temperatureof about 15 C. The

sulphonation mixture is run into water and sulpho-acid and oil areneutralized with ammonia. After removal of the unaffected part of theoil, having become separated by the dilution with water, the product isevaporated to a water content of 50%.. 816 grams of this product areobtained which, in this condition, contain 10.95% of ammonium sulphateand 10.60% of sulphur. It has been calculated that the sulphonated oilsubstance contains 2.8% of organic sulphur. The product is light-brown,transparent and clearly water-soluble.

Obviously, the various steps of the process may be modified considerablywith respect to the order and the number of steps and the specificmaterials used in the several methods exemplifying the refining andsulphonation steps, without departing from the spirit of the inventionsubstantially as described and claimed, and it is understood that I donot desire to limit myself to the specific embodiments shown in theforegoing examples.

What I claim as new, and on which I pray the issuance of Letters Patent,is:-

1. A process for producing clear, light-colored,

water-soluble sulphonation products of mineral oils naturally containingmore than two per cent of organically combined sulphur, withoutsubstantially impairing such natural organically combined sulphurcontent, which comprises selectively separating out of such oils theinherent resinifiable materials by treatment with a mineral acid of thegroup consisting of sulphuric acid and phosphoric acid, theconcentration of said refining acid being adjusted substantially withinthe range of 50 to 70 percent for sul-' phuric acid, according to thequality of the oil treated; subsequently carefully sulphonating thetreated oils at greatly reduced temperatures of C. and less withconcentrated sulphuric acid; thereafter dissolving out the solubleportion of the sulphur-rich sulphonation products thus obtained in waterand neutralizing the solution.

2. In a process for producing light colored water-soluble sulphonationproducts of mineral oils naturally containing more than two percent oforganically combined sulphur, the steps which comprise selectivelyseparating out of said oils the resinifiable materials withoutsubstantially impairing the organically combined sulphur content, byfirst treating the oil with sulphuric acid ofnon-sulphonating,concentration ranging from about 50 to 70%concentration, and subsequently treating the substantially de-resinifiedresidue with higher concentrations of the acid to effect sulphonation.

3. A process for producing light colored, water-soluble sulphonationproducts of Tyrolean shale oil having a relatively high natural sul-.phur content of over 2%, which comprises the after dissolving thesoluble portion of the sulphur-rich sulphonation products thus obtainedin water and neutralizing the solution with ammonia.

4. A process for producing light-colored, clearly Water-solublesulphonation products of Tyrolean shale oil having a'relatively highnatural sulphur content of more than 2%, which comprises the steps ofselectively separating out of said oils, before sulphonation, theinherent resinifiable materials without substantially impairing thenatural organically combined sulphur content by treating the oil firstwith 35% soda lye, then with 70% sulphuric acid, and then with fullersearth; sulphonating the oil with 96% sulphuric acid at about -8 0.,adding the sulphonation mixture to water and neutralizing thesulpho-acid and oil by treatment with ammonia; removing theunsulphonated oil which separates by dilution with the water, addingthereto an equal amount of new oil and about 10% more than an equal partof acid, stirring the mixture at about 15 C., running the sulphonationmixture into water, and neutralizing the su'lpho-acid and oil withammonia.

5. A process for producing light-colored, wa-

naturally containing more than 2% of organically combined sulphur whichcomprises the steps of selectively separating out of said oils the inherent resinifiable materials without substantially impairing thenatural organically combined sulphur by treating the oil first with 35%soda lye, then with 70% sulphuric acid, and then with fullers earth;sulphonating the treated oil with 96% sulphuric acid at about 8 C.thereafter dissolving the soluble portion of the sulphur-richsulphonation products thus obtained in water and neutralizing thesolution with ammonia.

ERICH ARNOLD WERNICKE.

-ter-soluble sulphonation products of mineral oils

